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arXiv · 2305.03692

Suppression of dark-state polariton collapses in cold-atom quantum memory

Katja Gosar·Vesna Pirc Jevšenak·Tadej Mežnaršič·Samo Beguš·Tomasz Krehlik·Dušan Ponikvar·Erik Zupanič·Peter Jeglič
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Abstract

We observe dark-state polariton collapses and revivals in a quantum memory based on electromagnetically induced transparency on a cloud of cold cesium atoms in a magnetic field. Using $\sigma^+$ polarized signal and control beams in the direction of the magnetic field, we suppress the dark-state polariton collapses by polarizing the atoms towards one of the stretched Zeeman states and optimizing the frequency detuning of the control beam. In this way, we demonstrate a quantum memory with only partial dark-state polariton collapses, making the memory usable at any storage time, not only at discretized times of revivals. We obtain storage time of more than 400 $\rm{\mu}$s, which is ten times longer than what we can achieve by trying to annul the magnetic field.

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Katja Gosar, Vesna Pirc Jevšenak, Tadej Mežnaršič, Samo Beguš, Tomasz Krehlik, Dušan Ponikvar, Erik Zupanič, Peter Jeglič. 2023-05-05. Suppression of dark-state polariton collapses in cold-atom quantum memory. https://doi.org/10.1103/physreva.108.032618

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